Super engineering plastics, such as aromatic polyamides, liquid crystal polyesters, and aromatic polyetherketone resins (polyaryletherketone resins), are known as a thermoplastic resin having excellent heat resistance and mechanical strength, while some super engineering plastics have poor light resistance. For example, various resin characteristics are often changed under a light environment (e.g., decrease in mechanical characteristics, and discoloration).
As a method for improving the light resistance, for example, addition of a widely used stabilizer (such as a light stabilizer or an antioxidant) has been examined. Unfortunately, the widely used stabilizer is thermally decomposed in the process of molding (fabrication) due to a very high melting point or a molding temperature (fabrication temperature) of the super engineering plastic, and the addition sometimes fails to sufficiently improve the light resistance. Further, in addition to the simple thermal decomposition, the resulting decomposition product of the stabilizer sometimes causes the resin to be more viscous and to have a lower heat resistance.
Japanese Patent Application Laid-Open Publication No. 2006-274073 (JP-2006-274073A, Patent Document 1) discloses a resin composition comprising (A) 70 to 99% by mass of a polyarylketone resin and (B) 30 to 1% by mass of a fluorinated resin, wherein the fluorinated resin (B) dispersed in the resin composition has an average particle diameter of 0.1 to 30 μm. This document also discloses that the resin composition provides a resin molded product having excellent sliding properties, solvent resistance, and heat resistance.
WO2012/005133 (Patent Document 2) discloses a resin composition for the purpose of improving sliding properties and impact resistance; the resin composition comprises an aromatic polyetherketone resin and a fluorinated resin, the fluorinated resin being a copolymer of tetrafluoroethylene and a perfluoroethylene unsaturated compound, the composition comprising the aromatic polyetherketone resin and the fluorinated resin at a mass ratio of 95:5 to 50:50, the fluorinated resin being dispersed as particles in the aromatic polyetherketone resin and having an average dispersed particle size of not more 3 μm.